Drill steel retaining device



Jan. 19, 1932. c. A. HULTQUIST 1,841,953

DRILL STEEL RETAINING DEVICE Filed Oct. 12. 1927 II 3 E 776,2. I .HJ I llllllm; I w IAHHIIII 1 ii g 1/ K j IN VEN TOR.

' ATTORNEY Patented Jan. 19, 1932 UNITED STATES PATENT OFFICE CHARLES A. HULTQUIST, F LOS ANGELES', CALIFORNIA, ASSIGNOR TO INDEPENDENT INEUMATIG TOOL COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE DRILL STEEL RETAINING DEVICE Application filed October 12, 1927. Serial No. 225,752.

My invention relates to rock drills and particularly to that class of drills in which the drill steel is loosely held and retained in the chuck by a steel retaining device.

The objects of this invention are: first, to

provide a simple, economical and particularly durable drill-steel retaining device for rock drills, which is made up of few simple parts v and one which will not be materially affected by vibrations of the rock drill or dislodged from its retaining position while the drill is in operation; second, to provide a device of this class in whichthe drill steel retaining member may be quickly shifted out of the way and clear of the drill steel fo r removing the latter and which is readily held in such out-of-the-way shifted position; third, to provide a device of this class in which the retaining member, pivotally mounted on a removable pivot pin, may be readily removed fourth, to provide a device of this class in which only a single spring is employed for yieldably retaining the drill steel and for absorbing the shock thereof when the same is forced outwardly at a time when the drill steel is not drilling or when the same is forced into a hole or soft formation; fifth, to provide a device of this class in which the retaining member is held in a retaining position by the inherent spring of the metal of the retaining member itself; sixth, to provide a device of this class in which the coil spring for holding the drill-steel retaining member inwardly is wholly inclosed and thus protected from injury, inoperativeness', and in efiiciency by the lodging of small rocks between the convolutions of the coil spring which often occurs by reason of the rough handling of i such machines around and 49 against rocks; seventh, to provide a device of this class in which the tension of the coil 7 spring holding the drillsteel retaining member inwardly cannot be readily changed, thus decreasing a common cause of breakage; and

eighth, to. provide as a whole a novelly constructed device of this class and one which is positive in its action, efiicient and which will not readily deteriorate or get out of order.

With these and other objects in view, as

Figure 1 is a fragmentary side elevational view of a drilling machine with my drillsteel retaining device mounted thereon and shown in a steel retaining position, a fragmentary portion of a drill steel being shown in the barrel of the machine; Fig. 2 is another elevational view thereof taken at a right angle to that of Fig. 1, and showing by dotted lines the drill-steel retaining member in an out-of-the-way position; Fig. 3 is a longitudinal sectional view thereof taken through 3-3 of Fig. 1; and, Fig. 4 is a lower end view thereof showing certain parts and portions broken away and in section to facilitate the illustration.

Like characters of reference refer to similar parts and'portions throughout the several views of the drawings.

The drilling machine or rock drill shown fragmentarily in the drawings is provided with a front or lower head 1 which is secured to one end of the body of the machine by any suitable means, such as by bolts 8. In the head 1 is mounted a chuck bushing 4: which is longitudinally broached at one end to receive one end of a drill steel, designated 5. This drill steel is provided with a collar or shoulder 5a near the end of the steel fitted into the bushing. This shoulder or collar prevents the steel from entering too far into the chuck bushin f and also prevents the steel from dropplng out of or from being forced from the bushing 4 when the drillsteel retaining member, designated 6, is in its operative or retaining position.

The retaining member (5 is substantially 5 U-shaped and consists of a lower or forward connecting portion 6a and a pair of spaced arms 6!) extending upwardly or backwardly from the connecting portion (5a. The connecting portion 6a is in the form of a yoke 10 and is adapted to partially encircle the drill 20 their ends with enlarged portions 6d which are pi vetally mounted at the extended ends ofa large pivot pin 7. This pivot pin extends transversely through the head 1 at one side of the axial line thereof and intermediate the ends of the head. and through a transversely extending boss 1a provided for this purpose. At the outer side of the head 1 isa spring housing 1?) which extends longitudinally with the axis of the head and from the boss 1a to the lower or forward end of the head. At the inner end of the housing 1?), which is provided with a longitudinal bore, is positioned a journal block 8 which is providod at its inner end with a substantially semi-circular seat 8a which conforms in ahpe to the curvature of the pin 7 and enthe same intermediate its ends Within the bore of the spring housing is positioned a compression coil spring 9 which engages at one end the outer end of the journal block 8 and at the opposite end a screw lug 10 screwed into the end of the bore 0 the spring housing. This plug 10 retains the W in position, as well as compresses the same against the journal block and forces the journal block against the pivot pin. The screw plug 10 is preferably provided with a collar 10a at its outer end so that the plug may be screwed inwardly to a positive shoulder, preventing, without other means, the increasing of the compression of the s and thus reducing to a minimum the likelihood of breaking the spring. The transverse hole in the boss 10 through which the pivot pin 7 extends is elongated with respect to the longitudinal axis of the head at the opposite sides of the journal block 8 so that the pivot pin may be forced downwardly a slight distance when the abutment or yoke 6a is engaged by the shoulder on the drill steel. At the opposite ends of the pivot pin 7, are provided cotter pins 11 which prevent the upper or backwardly extended arms of the retaining member from moving too far outwardly and for preventing the pivot pin from dropping out. The retaining member 6 is held in a drill-steel retaining position by a pair of rounded lugs 10 positioned at dian'ietrically opposite sides of the head and extended in a longitudinal direction therewith. These lugs are adapted to enter correspondingly shaped recesses at the inner sides and intermediate the ends of the arms 66 of the retaining member. The recesses 66 are, however, extended longitudinally a distance considerably greater tihanltlre length of the lugs 10 so as to permit the retaining member to be shifted longitudinally with respect to the longitudinal axis of the head, as shown in Figs. 1 and 2. Thus, when the retaining member is shifted into operative position, as shown by solid lines in Fig. 2, the arms 6?) are forced outwardly by the engagement therewith of the lugs 1 until said lugs enter the recesses 66, when said arms again spring into their origin-al contracted positions, as shown in Fi s. 1 and 4. The retaining member may e moved about its pivotal axis away from the drill steel as far as desired. but the movement thereof in the opposite direction, or toward the drill steel, is limited by a pair of lugs 1d which extend outwardly from the head 1 at the lower or forward end thereof and are adapted to be engaged by the edges of the arms 6?) nearest the open side of the yoke 6a., as shown in Figs. 1, 2 and 4. It will be here noted that the arms 6?) of the retaining member are fiat with the inner fiat sides adjacent the head; the flat construction of said arms facilitates the outward bending thereof either at the portion secured to the yoke or throughout its length so that said arms may be readily bent in order to shift the same over or disengage the same from the lugs 10.

Though I have shown and described a particular construction, combination and arrangement of parts and portions, I do not wish to be limited to this construction, combina/tion and arrangement, but desire to include in the scope of my invention the construction. combination and arrangement substantially as set forth in the appended claim.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

The combination with the barrel of a drilling machine and a drill steel in the barrel, of pivot means positioned ofi' center with respect to and extending to the opposite sides of the barrel. a drill-steel retainer having a portion at the end of said barrel engagable by said drill steel and having arms extending substantially straight from the portion engageable with the drill steel to the sides of the barrel and positioned substantially in a plane passing through the axis of the drill steel, said arms being offset angularly at their ends and pivotally mounted at said ends on said pivot means, and lug means on the barrel adapted to be engaged by the straight portions of the arms of the retainer for positively limiting the shifting of said retainer about its pivotal axis toward said drill steel and for causing the pull on the retainer to be a substantially direct pull on the portion of the retainer beyond the lug means.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 7th day of October, 1927.

CHAR-LES A. HULTQUIST. 

